This invention relates to a needle motion mechanism in scoop-stitch machines which permits full penetration of a needle into cloth even in the shoulder part with thick pads so that a beautiful seam may be obtained in method of hemming on the sleeve lining in the shoulder part of a coat.
In the prior art of hemming on the sleeve lining in the shoulder part of a coat such as a business suit, thick pads in the shoulder part have made it difficult to fully push up the shoulder part from the opening of the needle plate.
Thus, in methods of hemming on the sleeve lining in the shoulder part of a coat, hand sewing has conventionally been employed. Alternatively, sewing from inside the cloth has been employed using sewing machines specially for stitching bulky materials, or conveniently, scoop-stitch sewing machines have been used first for scoop-stitching from inside and then after the lining is turned over. However, these widely used methods of machine sewing do not provide complete hemming on, for example, the sleeve lining in the shoulder part of a coat. Furthermore, the above procedures require much time and labor, reducing operational efficiency to a great degree.
In a scoop-stitch sewing machine, a curved needle is supported on the end of a pivoting arm, and the needle is swung in a fixed arc into engagement with fabric which is pushed up between spaced needle plates. The present invention relates to improvements in scoop-stitch sewing to assure good penetration of the needle into thick fabrics.